A.A quick answer is, "their lawyers." For the same reason that a product we used to call a "vapor barrier" is now called a "vapor retarder," many products are now sold for dampproofing rather than for waterproofing.

A product that fills the pores of a material to reduce capillary movement of water through the material can only be called dampproofing. An example is the thin bituminous coating painted on primarily to reduce vapor flow through the wall. These products are useless when bulk water presses against the wall. If the product produces a sealed...

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